impact of 4d modeling on construction planning process - Chalmers ...

3.2.4.1 4D Modeling Processes
Variety <strong>of</strong> tools and processes for building 4D models are available to the scheduler to
choose from listed below.
1. Manual method using 3D or 2D tools
2. Built-in 4D features in a 3D or BIM tool
3. Export 3D/BIM to 4D tool and import schedule
Manual CAD-Based Methods
Colored pencils and drawings, with different colors to represent different sequences to
show progress <strong>of</strong> work with time have been used by construction planners for
decades. This process was shifted to CAD drawings by the planners with the advent <strong>of</strong>
CAD. Planners worked with a third party to create rendered animations to visually
present the schedule in most <strong>of</strong> the cases. These animations are very appealing
visually and tend to be a very effective marketing tool, but they are an inadequate
scheduling and planning tools. The main reason for this is the manual production <strong>of</strong>
the animations with limited options to change, update, and do real time scenario
planning. With every change in schedule detail, the planner must create a new set <strong>of</strong>
images or animations to manually resynchronize the 4D image with the schedule. Due
to these limitations, the use <strong>of</strong> these tools is normally restricted to the initial stages <strong>of</strong>
the design when visualizations <strong>of</strong> the construction process play an important role and
is much desired by the clients (Eastman, Teicholz, Sacks, & Liston, 2011).
BIM Tools with 4D Capability
Another way to generate 4D images is through features that automatically filter the
objects in the view on the bases <strong>of</strong> the parameters set. Revit is one such tool which
distributes the objects into several phases according to the requirement. The user can
then apply filters to view the desired object in a specific phase. This type <strong>of</strong> 4D
functionality is applicable to basis phasing and generation <strong>of</strong> 4D images at desired
requirements but does not provide direct integration with the project schedule.
Whereas, Tekla Structures, a BIM tool, provides a built-in scheduling interface
enabling multiple links between the physical objects and the activities in the model. A
single physical object can be linked to one or several activities and a single activity
can be linked with one and several physical objects making the 4D evaluation <strong>of</strong>
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CHALMERS, Civil and Environmental Engineering, Master’s Thesis 2012:27